[RideZX6R]

A quick bit of context: I have a car that started as an SS1LE that now has an NA 427 making 650whp, I road race this car and find that 5th is so long the car is falling on it's face a bit. I'd like to get a shorter 5th... The ZL1 offers this (so does the ZLE but that has a shorter 6th as well and I simply don't need or want that).

I've found a trans and a shop willing to do the work by my concern is any different sensors, mounting points, connectors, etc that might be different?

Anyone aware of differences or able to look up factory info?

[PJS57]

Gear ratios are different for everything except 4th gear in the ZL1 and SS:


SS gears:


1st: 2.66
2nd: 1.78
3rd: 1.30
4th: 1.0
5th: 0.75
6th: 0.50


ZL1 (non-1LE):


1st: 2.29
2nd: 1.61
3rd: 1.21
4th: 1.0
5th: 0.82
6th: 0.54




AFAIK the mounting points & connections are all the same. The hard part is going to be getting your ECU to recognize the different gears. I know some guys have changed made this swap and even changed gear ratios in the tuning tables, but have reoccurring issues where the car thinks the clutch is slipping because it's not getting the right RPM/Speed ratio the ECU is looking for. That part is out of my wheelhouse, and is what is keeping me from doing the same swap on my car.

Coming from the mustang world I know the ZL1 gear stack is the way all the fast guys (like Phoenix racing in SCCA) go with their coyote track builds. It keeps the car in the peak power band, and makes for faster lap times. Wish the SS 1LE came with that transmission from the factory for that reason but I'm sure there's calibration & emission costs that kept that from happening.

[Bumbleboy92]

Here's my chart for transmission/differential information

As PJS57 said, the gears are different between SS and ZL1, I'm unsure if the SS 1LE is the same or not, I know the SS/LT1, ZL1, and ZL1 1LE differential ratios I have are for the regular cars but do not know if they apply to the 1LE variants